Today, auxiliary operating facilities for fuel-electrically driven vehicles are mainly employed in diesel-electric locomotives or large diesel-electric mine vehicles, where the auxiliary operating facilities are constructed as fans, air-conditioning systems, actuators, on-board network converters etc. Such auxiliary operating facilities are popularly fed by means of a suitable device. Such a device for the feeding of auxiliary operating facilities for a fuel-electrically driven vehicle is for example mentioned in the U.S. Pat. No. 6,087,791 and in the DE 200 01 113 U1. In it the device has a combustion engine, a generator driven by the combustion engine and a rectifier connected with the generator on the AC voltage side. On the DC voltage side the rectifier is connected with a first and a second connection of a DC voltage circuit. In addition, with the device according to DE 200 01 113 U1, a multiplicity of inverters is connected to the first and second connection of the DC voltage circuit, which inverters each supply the relevant auxiliary operating facility such as for example fan, air-conditioning system, actuator, on-board network converter etc. with electric energy. According to the U.S. Pat. No. 6,087,791 and the DE 200 01 113 U1 a drive inverter is also connected to the first and second connection of the DC voltage circuit, which drive inverter on the AC voltage side feeds one or several drive motors of the vehicle.
It is also conceivable that a second rectifier connected with a generator is provided. The second rectifier is then connected on the DC voltage side with a first and a second connection of a second DC voltage circuit, while a second drive inverter is connected to the first and second connection of the second DC voltage circuit, which second drive inverter on the AC voltage side feeds one or several drive motors of the vehicle.
Since the power requirement of such drive motors is very high, a DC voltage of several kilovolts is typically present between the first and the second connection of the DC voltage circuit in order to be able to provide the appropriate power. Problematic in this context with the device for the feeding of auxiliary operating facilities for a fuel-electrically driven vehicle of the U.S. Pat. No. 6,087,791 and the DE 200 01 113 U1 is that the inverters connected to the first and second connection of the DC voltage circuit have to be designed to the high DC voltage mentioned above, i.e. the power semiconductor switches of the respective inverters have to have a high blocking capability and suitable protective facilities and operating methods specifically adapted to these. The construction of the inverters is thus highly complicated, susceptible to faults and accordingly requires a lot of space. In addition, insulation distances of the supply lines and rails to the inverters and between the inverters themselves have to be maintained, which requires additional space. This complicated and space-intensive construction of the inverters and the device for the feeding of auxiliary operating facilities consequently causes major expenditure in terms of installation and maintenance. Especially a simple, compact and robust construction of the device for the feeding of auxiliary operating facilities however is extremely desirable with a fuel-electrically driven vehicle.
In the DE 94 13 638 U1 a device for the feeding of auxiliary operating facilities for a fuel-electrically driven vehicle is also disclosed, which device has a first combustion engine and a first generator driven by the first combustion engine. On the AC voltage side with the first generator, a first rectifier assigned to the first generator is connected, wherein a first step-down converter is connected downstream of the first rectifier. An assigned first DC voltage circuit is connected downstream of the first step-down converter with which first DC voltage circuit a first inverter for the feeding of auxiliary operating facilities is connected. In addition to this, the device of the DE 94 13 638 U1 has a second combustion engine and a second generator driven by the second combustion engine. On the AC voltage side a second rectifier assigned to the second generator is connected to the second generator while a second step-down converter is connected downstream of the second rectifier. An assigned second DC voltage circuit is connected downstream of the second step-down converter with which second DC voltage circuit a second inverter for the feeding of auxiliary operating facilities is connected.